The present invention relates to surgical methods and apparatuses for ultrasonically fragmenting and aspirating, and electrosurgically coagulating and electrosurgically cutting tissue at an operative site on a patient.
The application of ultrasonically vibrating surgical devices used to fragment and remove unwanted tissue with significant precision and safety has led to the development of a number of valuable surgical procedures, and the use of ultrasonic aspirators for the fragmentation and surgical removal of tissue from a body has become well known. Initially, the technique of surgical aspiration was applied for the fragmentation and removal of cataract tissue as shown, for example, in U.S. Pat. Nos. 3,589,363 and 3,693,613; the contents of these patents and each of the other patents and documents mentioned herein are hereby incorporated by reference in their entirety. Later, such techniques were applied with significant success to neurosurgery and other surgical specialties where the application of ultrasonic energy through a small, handheld device for selectively removing tissue on a layer-by-layer basis with precise control has proven feasible. Recently an ultrasonic aspirator for the endoscopic removal of compliant biological tissue as described in International Publication No. WO 87/01276 has become known.
Certain devices known in the art characteristically produce continuous vibrations having a substantially constant amplitude at a frequency of about twenty to about thirty KHz up to about forty to about fifty KHz. U.S. Pat. No. 3,589,363 describes one such device which is especially adapted for use in the removal of cataracts, while U.S. Pat. No. 4,063,557 describes a device suitable for removal of soft tissue which is particularly adapted for removing highly compliant elastic tissue mixed with blood. Such devices are continuously operative when the surgeon wishes to fragment and remove tissue, and generally operate under the control of a foot switch.
One known instrument for ultrasonically fragmenting tissue at an operative site and then aspirating the tissue particles and fluid away from the site is the CUSA Model System 200 ultrasonic aspirator which is manufactured and sold by Cavitron Surgical Systems of Stamford, Conn.; see also U.S. Ser. No. 847,301. When the longitudinally oscillating metallic tip thereof is contracted with tissue it gently, selectively and precisely fragments and removes the tissue. Some of the advantages of this unique surgical instrument are that there is little resulting damage to healthy tissue in a tumor removal procedure, blood vessels can be skeletonized, healing of tissue is promoted, no charring or tearing of margins of surrounding tissue results, only minimal pulling of healthy tissue is experienced, and excellent tactile feedback for selectively controlled tissue fragmentation and removal is provided.
Surgeons using the CUSA ultrasonic surgical instrument have indicated a desire for additional and improved capabilities for this instrument. In particular they have requested provisions for controlled penetration of capsular membranes without damage to the organs, precise and rapid removal of fibrous tissue structures such as in mucosal proctectomy procedures, and an increased rate of tissue fragmentation and removal. During many surgical procedures wherein ultrasonic fragmentation instruments have been employed additional instruments have been required for tissue cutting and hemostasis at the surgical site. Hemostasis is needed for example in desiccation techniques for deep coagulation to dry out large volumes of tissue and also in fulguration techniques for spray coagulation to dry out the surfaces of tissues. See, e.g. U.S. Pat. No. 4,378,801. Often an electrosurgical pencil plugged into an electrosurgical unit for tissue cutting and hemostasis and a suction probe for aspiration of fluids and cut tissue particles are used. Since many surgical tools are thereby required at a single surgical site, the total surgical time is increased, and efficiency decreased, as the surgeon must switch among different instruments. Also, undesirable amounts of blood are lost because of the time needed to switch from a cutting or fragmenting tool to a cauterizing instrument when bleeding is observed. Additionally, by simultaneously maintaining a plurality of surgical devices at the operative site the surgeon's field of view is reduced. Further due to the complexity of the procedures false activation of the electrosurgical pencil when not in use causing an RF burning of the patient can occur, and meet the desires and needs of the surgeons.
Accordingly, a need has arisen for improved surgical procedures and apparatuses which remedy these problems, and meet the above-expressed desires and needs of the surgeons.